:root {
    --color-primary: #334155;
    --color-primary-dark: #0f172a;
    --color-accent: #3b82f6;
    --color-surface: #f8fafc;
    --color-text: #1e293b;
    --rgb-primary: 51,65,85;
    --rgb-accent: 59,130,246;
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 14px;
    --radius-xl: 20px;
    --shadow-sm: 0 1px 2px rgba(15,23,42,.07), 0 1px 3px rgba(59,130,246,.05);
    --shadow-md: 0 4px 12px rgba(15,23,42,.12), 0 2px 6px rgba(15,23,42,.08), 0 0 0 1px rgba(59,130,246,.04);
    --shadow-lg: 0 12px 24px rgba(15,23,42,.16), 0 4px 10px rgba(15,23,42,.12), 0 0 0 1px rgba(59,130,246,.08);
    --space-section: 1.75rem;
    --space-card: 0.875rem;
    --space-gap: 0.625rem;
    --transition: 0.5s cubic-bezier(0.22, 1, 0.36, 1);
    --heading-weight: 700;
    --body-line-height: 1.65;
}

/* 基础覆盖 */
body {
    color: var(--color-text);
    line-height: var(--body-line-height);
    background: linear-gradient(180deg, #f8fafc 0%, #e2e8f0 55%, #cbd5e1 100%);
}
h1, h2, h3, h4 { font-weight: var(--heading-weight); }
section, .section { padding-top: var(--space-section); padding-bottom: var(--space-section); }
.card, [class*="card"] {
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    padding: var(--space-card);
    transition: var(--transition);
    background: linear-gradient(145deg, #ffffff 0%, #f8fafc 100%);
}
.btn, button[class*="btn"], a[class*="btn"] {
    border-radius: var(--radius-md);
    transition: var(--transition);
    background: linear-gradient(135deg, #3b82f6, #2563eb);
    color: #fff;
    box-shadow: 0 4px 12px rgba(59,130,246,.3);
}
a:not([class]) { color: var(--color-primary); transition: var(--transition); }

/* ========== Section Layout Variants ========== */

/* news: list-view */
/* 列表模式 (图左文右) */
                .news-grid { display: flex; flex-direction: column; gap: var(--space-gap); }
                .news-grid .card { display: grid; grid-template-columns: 280px 1fr; }

/* features: grid-2 */
.feature-list { display: grid; grid-template-columns: repeat(2, 1fr); gap: calc(var(--space-gap) * 1.5); }

/* hero: left-aligned */
.hero-content { text-align: left; max-width: 600px; }

/* testimonials: carousel */
/* 单条轮播 */
                .testimonial-list { display: flex; overflow: hidden; } 
                .testimonial-list > * { flex: 0 0 100%; }

/* partners: centered */
.partner-grid { display: flex; flex-wrap: wrap; justify-content: center; gap: 1.75rem; }

/* faq: with-sidebar */
/* FAQ 左 + 联系信息右 */
                .faq-wrapper { display: grid; grid-template-columns: 2fr 1fr; gap: 1.75rem; }

/* stats: big-number */
/* 大数字居中 */
                .stats-grid { display: flex; flex-wrap: wrap; justify-content: center; gap: 1.75rem; }
                .stats-grid .stat-value {
                    font-size: 3rem;
                    color: var(--color-accent);
                    text-shadow: 0 2px 10px rgba(59,130,246,.25);
                }

/* cta: full-bg */
.cta-section {
    background: linear-gradient(135deg, #1e293b 0%, #334155 55%, #3b82f6 100%);
    color: #fff;
    padding: 3.5rem 1.75rem;
    box-shadow: inset 0 -4px 16px rgba(15,23,42,.3), 0 8px 24px rgba(15,23,42,.2);
}

/* Page Layout: full-width */
/* 无侧边栏, 全宽 */
            .page-main { max-width: 1200px; margin: 0 auto; }

/* 条件性装饰 */
.card:hover, [class*="card"]:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
a:not([class]):hover { color: var(--color-accent); }
.card {
    border: 1px solid transparent;
    background:
        linear-gradient(145deg, #ffffff 0%, #f8fafc 100%) padding-box,
        linear-gradient(135deg, rgba(59,130,246,.5), rgba(51,65,85,.15), rgba(59,130,246,.08)) border-box;
    background-origin: border-box;
    background-clip: padding-box, border-box;
}
header, .header, .navbar {
    background: linear-gradient(90deg, #0f172a 0%, #1e293b 45%, #334155 100%);
    color: #f8fafc;
    box-shadow: 0 4px 16px rgba(15,23,42,.25), 0 1px 3px rgba(59,130,246,.15);
}

/* Responsive */
@media (max-width: 1024px) {
    .news-grid { grid-template-columns: repeat(2, 1fr) !important; }
    .feature-list { grid-template-columns: repeat(2, 1fr) !important; }
    .partner-grid { grid-template-columns: repeat(3, 1fr) !important; }
    .stats-grid { grid-template-columns: repeat(2, 1fr) !important; }
    .hero-inner { grid-template-columns: 1fr !important; }
}
@media (max-width: 640px) {
    :root { --space-section: 1.75rem; --space-card: 0.875rem; --space-gap: 0.625rem; }
    .news-grid { grid-template-columns: 1fr !important; }
    .feature-list { grid-template-columns: 1fr !important; }
    .faq-list { grid-template-columns: 1fr !important; }
    .testimonial-list { column-count: 1 !important; }
    .partner-grid { grid-template-columns: repeat(2, 1fr) !important; }
    .stats-grid { grid-template-columns: repeat(2, 1fr) !important; }
    .cta-inner { grid-template-columns: 1fr !important; }
}